SOLUTION: Can you please help me solve this problem? (2 times the cube root of 16)-(4 times the cube root of 54)

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Question 190599: Can you please help me solve this problem? (2 times the cube root of 16)-(4 times the cube root of 54)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
2%2Aroot%283%2C16%29-4%2Aroot%283%2C54%29 Start with the given expression.


2%2Aroot%283%2C8%2A2%29-4%2Aroot%283%2C54%29 Factor 16 to get 8%2A2. Note: 8 is a perfect cube.


2%2Aroot%283%2C8%2A2%29-4%2Aroot%283%2C27%2A2%29 Factor 54 to get 27%2A2. Note: 27 is a perfect cube.


2%2Aroot%283%2C8%29%2Aroot%283%2C2%29-4%2Aroot%283%2C27%29%2Aroot%283%2C2%29 Break up the roots.


2%2A2%2Aroot%283%2C2%29-4%2A3%2Aroot%283%2C2%29 Take the cube root of 8 to get 2


4%2Aroot%283%2C2%29-12%2Aroot%283%2C2%29 Take the cube root of 27 to get 3


%284-12%29%2Aroot%283%2C2%29 Factor out the GCF root%283%2C2%29


-8%2Aroot%283%2C2%29 Combine like terms.


So 2%2Aroot%283%2C16%29-4%2Aroot%283%2C54%29=-8%2Aroot%283%2C2%29